Recently, hybrid electric vehicles (HEVs) have much drawn attention as eco-friendly vehicles.
Typically, a hybrid electric vehicle (HEV) refers to a vehicle that uses two power sources together. The two power sources are mainly an engine and an electric motor. HEVs are recently under vigorous development because HEVs are superior to vehicles provided with an internal combustion engine alone in terms of fuel efficiency, power performance, and exhaust gas reduction. Among HEVs, in the case of a plug-in hybrid electric vehicle (PHEV), a plug is connected to the PHEV and thus a battery to drive an electric motor may be charged with external power.
The HEV may include a cluster provided with a gauge (hereinafter referred to as an eco-gauge for convenience of description) for indicating whether an electric motor charges a battery or drives wheels, and a degree of corresponding action. The eco-gauge may be a dial-type gauge or a bar-type gauge. The eco-gauge may acquire information regarding the position of a needle to be used for measurement from a hybrid controller. The hybrid controller may be a high-order controller to be used for overall control of a powertrain of a hybrid electric vehicle (HEV).
A structure and problems of the eco-gauge will hereinafter be described with reference to FIG. 1.
FIG. 1 is a view illustrating the structure and problems of a dial-type gauge of a general hybrid electric vehicle (HEV).
Referring to FIG. 1, an eco-gauge 100 of the HEV may mainly include a needle 110 and a gauge region 120 in which the needle 100 moves. The gauge region 120 may include a charging region 123 indicating charging of the motor, and a driving region 125 indicating driving of the motor. The charging region 123 and the driving region 125 may be respectively disposed at left and right sides with respect to a zero point 121. If engine ignition is turned off (IG OFF), the needle 110 may stay at the lowest point 127. In this case, the driving region may be classified into an eco-region 125-1 and a power region 125-1. If the powertrain operates in the range of a high-efficiency operating point, the needle 110 is located in the eco-region 125-1. The needle 100 may gradually move toward the power region 125-2 in proportion to the increasing output of the powertrain. Therefore, the eco-region 125-1 may enable a vehicle driver to drive a vehicle with fuel efficiency while simultaneously recognizing the position of the needle 110.
However, the eco-region 125-1 is fixed in size or position, irrespective of a vehicle driving state. In fact, although the range of a high-efficiency operating point of the powertrain is changed, the vehicle driver who uses the aforementioned dial-type gauge is unable to recognize change of the high-efficiency-driving-point range.